Ethanolamine → Methyl 4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

HRID 14218

Reaction equation

HRID 14218 reaction equation
[CH2:1]([N:5]1[C:10]2[CH:11]=[C:12]([C:15]([O:17][CH3:18])=[O:16])[CH:13]=[CH:14][C:9]=2[O:8][CH2:7][C:6]1=O)[CH2:2][CH2:3][CH3:4].B1C2CCCC1CCC2.C(CN)O>O1CCCC1>[CH2:1]([N:5]1[C:10]2[CH:11]=[C:12]([C:15]([O:17][CH3:18])=[O:16])[CH:13]=[CH:14][C:9]=2[O:8][CH2:7][CH2:6]1)[CH2:2][CH2:3][CH3:4]

Participants

5

Reactant 3

HCID 700EthanolamineHCID 789669-Borabicyclo(3.3.1)nonaneHCID 21086200Methyl 4-butyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

Product 1

HCID 21086198Methyl 4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylateYield 80.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of methyl 4-butyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate (800 mg) and 9-BBN (1.6 g) in tetrahydrofuran (13 mL) was refluxed for 1.5 h. The mixture was cooled to room temperature, ethanolamine (0.4 mL) was added, and the resulting solution was concentrated under reduced pressure. The residue was washed with hexanes, filtered, and the filtrate was concentrated under reduced pressure. Purification by flash column chromatography (silica, 25% ethyl acetate/hexanes) afforded 607 mg of the title compound: 1H NMR (300 MHz, DMSO-d6) δ 7.21, 7.16, 6.75, 4.24-4.21, 3.78, 3.34-3.24, 1.55-1.47, 1.38-1.30, 0.95-0.90.

Workup

  1. concentrationthe resulting solution was concentrated under reduced pressure
  2. washThe residue was washed with hexanes
  3. filtrationfiltered
  4. concentrationthe filtrate was concentrated under reduced pressure
  5. customPurification by flash column chromatography (silica, 25% ethyl acetate/hexanes)

Sources & evidence

ORD record
ord-080904ae1a3f43bd8361146e18e6f260
Source dataset
uspto-grants-2010_06
Patent number
US07727997B2

Linked notes

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